In his book ‘The Pigeon Tunnel’ John le Carré includes a preface that describes him being taken by his father to Monte Carlo on a gambling spree.
Near an old casino was a sporting club that had a length of lawn which included a shooting range that looked out to sea. Under the lawn ran small parallel tunnels leading to the sea in which live pigeons are inserted that had been hatched and trapped on the casino roof. Their task was to flutter their way along the dark tunnel and appear in the sky as targets for gentlemen waiting to shoot them down. Those pigeons that were missed or wounded do what pigeons do and returned to their birth on the casino roof where those same traps awaited them.
It serves to provide an analogy of the Cornish electorate at the ballot box. They vote for the Westminster parties only to be shot down by those same parties that continually fails them. They do what the Cornish do and return to the ballot box, election after election, and do exactly the same thing only to be failed again.